Cameras & Camera-Driven Rendering
Examples where the camera drives what gets rendered.
| Example | Run command | What it shows |
|---|---|---|
culling |
cargo run -p wsg-lib --example culling |
GPU-driven frustum culling: a 15×15 grid of cubes, off-frustum objects skipped |
All commands run from the repo root.
The frustum is defined by the camera's view-projection matrix, so frustum culling is inherently a camera concept: move the camera and the set of drawn objects changes — with zero CPU cost (the GPU decides in a compute pass).
culling — GPU Frustum Culling
A grid of 15×15 = 225 cubes is placed on a large floor. The GPU-driven culling (compute shader) determines which cubes are visible in the camera frustum and zeros their indirect draw args — zero CPU cost.
cargo run -p wsg-lib --example culling
Keys
| Key | Action |
|---|---|
| Drag (LMB) | Orbit camera (look around) |
| Wheel | Zoom in/out |
R |
Reset (top view) |
1 |
Front view (cubes behind are culled) |
2 |
Side view |
3 |
Top view (see the full grid) |
What to observe
- In top view (
3): the entire grid is visible. - Orbit to 90°: cubes behind the camera are not drawn (culled).
- Zoom very close: only cubes near the near plane are rendered.
- Cubes rotate slowly (staggered phases) → culling is dynamic (a cube can enter/leave the frustum during a frame).
Note
: culling is enabled via
AppBuilder::with_culling(true). Changing it tofalsein the source disables culling (all cubes are always drawn, even off-screen).The GPU-driven pipeline (compute matrices → culling → indirect draws) is documented in
docs/tech/ARCHI_CPU_GPU.mdanddocs/user/gpu-driven.md.